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On the outer coasts of the Highlands gusts of 100 m.p.h. occur from time to time, and in certain places, where the configuration of the hills governs the play of wind, there are freak gusts and up and down draughts of excessive strength. In December 1938, I was going over the hill of North Rona during a three-day southerly gale to fetch water from the well on the southern cliff face. The wind was not so bad as it had been in the night, but I had to go on hands and knees over the ridge at 300 feet, from which there was an unbroken downward sweep to the sea on the south. When I reached the edge of the 70-foot cliffs which were at an angle of 30° from the vertical, I saw the turf at the edge of the cliff being lifted like the edge of a blanket, and the outer fringes of it were being torn off and flung inland just as a blanket would wear in a wind. All this is common enough in the islands; I had seen it before. But a few yards inland I saw two bare patches in the turf where two boulders had rested for years; the black surface of the bare patch was a good inch below the turf, and the boulders themselves—a foot to eighteen inches across and about eight inches high—were rolled uphill a distance of about three feet. The seals might well have shifted them had they been there, but no seals wandered in that part of the island. Only the force of the wind could have moved those stones, and as I still cannot believe that any wind we know could turn up the dead weight of a boulder well set with a flat bottom in the turf, presumably the cliff being set at that angle had the effect of multiplying the force of the wind at the upper edge; and a fairly large area of turf must have been lifted and stretched in some of the gusts, with the result that the boulders would be thrown out of their sockets uphill. The effect of wind is much less farther inland from the sea. The tree line on the coasts may be no more than 200 feet—assuming that trees will grow at all—whereas it is 1,800 feet on the western side of the Cairngorms. The prevailing wind in the Highlands is from the south-west. Such winds come off the relatively warm waters of the North Atlantic Drift and are laden with moisture. The weather is rarely cold during the time they blow. If the observer is far enough out from the high hills to see what is really happening in the sky, he will note that the south-westerly gales are predictable from the movements of the clouds before the wind is felt at sea level, or he may see a great bank of cloud out to the west in the Atlantic the night before. The south-westerly gales are gusty even out on the coasts, but they are so moisture-laden that one’s sense of smell is heightened: earth and sea have a beauty of their own at such a time through the scents they convey. The observer is watching the sky for signs of the end of the gale and sees a break of blue sky for a moment; then he notices that the clouds are no longer moving from the south-west but from the west. Soon he feels the wind to be coming from the west at sea level and the clouds are moving from north-west. Finally the wind veers farther to north-west and falls light in the north. That is the end of the gale.
The trough of low barometric pressure is left behind and the recording needle marks a steady rise and then levels off as the wind reaches the north. These gales have a closely similar pattern: in winter they may last several days; or only twenty hours in summer, sometimes completing the pattern day after day, beginning in the early morning with short gusts which are the forerunners and falling light in the late evening. It is the West Highland coast which shows up these gales as if under a magnifying glass. They will be mere breezes a few miles inland or at the head of a sea loch. Only their raininess will be felt there. The barograph shows less pronounced movement also, back in from the coast.
It is obvious that the effect of wind on the outer coasts is very great, for there is not only the period of great gales in the winter, when there are no leaves on the shrubs and no leafy vegetation at ground level, but there is the continual wearing of the summer period. I have seen leaves die from shaking through three days of blowing. Such trees as exist take on a distorted appearance, not one branch or twig managing to survive on the windward side of the trunk. It is a remark commonly heard that a tree has been bent by the constant action of the wind, but this is not true. Distortion is brought about by the continual lack of survival of all growth on one side. The distal ends of twigs are killed and the tree develops more and more a fuzziness of short annual shoots from the main stem. The influence of wind on the coastal region is further complicated by the spray which it may carry, for most broad-leaved plants object to a deposition of salt on their foliage. This is a subject we shall touch on later in the book.
North winds are relatively uncommon in the Highlands, but are recognized as bringers of snow in winter, snow which sets up its own train of events in natural history. A north wind in June or July means the best of sunny weather, but in August the north wind brings rain. East winds blow most regularly in spring, but gales from the south-east occur as well in the West Highlands. They are very cold for the district, as the south wind can be as well, for the air has come over a mountainous region where it must become chilled. The southeasters are dry winds and have a desiccating effect on the autumn herbage, sufficient to curtail the grazing season in some years. The south winds of summer mean a leaden sky and rain.
To conclude, the climate of the Scottish Highlands and Islands is rapidly changeable and far from uniform. The coastal climate is maritime or oceanic, but in the Central and Eastern Highlands it is more continental—more extreme temperatures, less wind, less rain and drier air. The meteorological tendency to drier air in the central region and the Dee Valley is further added to by the capacity of the ground to drain rapidly.
CHAPTER 2 (#ulink_3f79c5f4-a1a5-5573-8075-0730565f6e99)
RELIEF AND SCENERY
LET US look at a physical map of Scotland and allow ourselves to make a tour of the Highlands as observers of country rather than as naturalists making detailed studies of habitats. We shall then be able to see those habitats with eyes wider open for the comparative sense we shall have gained. It will be convenient to divide the Highlands into five zones to which we cannot fairly give definite boundaries, though the zones themselves are significant in natural history. The divisions are my own and do not carry the weight of the acceptance of a committee of biologists. I should call them:
1 The southern and eastern Highland fringe which is in effect a frontier zone.
2 The Central Highlands, which may be likened to a continental or alpine zone.
3 The Northern Highlands, a zone with sub-Arctic or boreal affinities.
4 The West Highlands south of Skye, which may be called the Atlantic or Lusitanian Zone.
5 The Outer Hebrides and islands of Canna, Coll, Tiree, and such small islands as the St. Kilda group, the Treshnish group, the Flannans, North Rona and Sula Sgeir; an oceanic zone.
THE SOUTHERN AND EASTERN HIGHLAND FRINGE
FIG. 4.—Generalized relief features of the Highlands By courtesy of the Land Utilisation Survey of Great Britain
This zone follows the line of the Highland Border Fault from Helensburgh almost to Stonehaven, and then turns at right angles north-westwards to include the middle Dee. The Lochnagar massif, 3,786 feet, may properly belong to the Central Highland zone, but it is a good pivotal point and its long southern slopes all drain into the eastern plain below the Highland Border Fault. From Lochnagar we can cross to Pitlochry and thence to Loch Tay and south-westwards to the head of Loch Lomond and to the sea at the head of Loch Fyne.
The land to the south and east of this zone is highly productive agricultural ground which shows some of the best farming in Scotland.
The zone itself is largely occupied by sheep farms which graze the Blackface breed, but the farther north-eastwards we go from Cowal to the Glens of Angus the better are the sheep, and the same hills on which they graze become easier and better grouse moors. That part of the zone east of the Tay Valley has a very high value as grouse moors for they are among the best in the kingdom. There are also deer forests in the area—west of Loch Lomond where cattle and sheep are also grazed, the Forest of Glenartney, south of Loch Earn and east of Loch Lubnaig, and Invermark Forest south of Lochnagar and in the upper reaches of the Glens of Angus.
The changing nature of this zone within historical time may be gathered from such names on the maps as Forest of Alyth and Forest of Clunie. There would be a large number of trees there hundreds of years ago, but the word forest would be given in the particular connotation of a large uncultivated tract, a usage of the word with which we are more familiar in the Highlands where a deer forest may be practically treeless. The Forests of Clunie and Alyth are now places of rearing farms for cattle and sheep, though, of course, there are still large areas of grouse moor. The golden eagle has gone from here, no longer tolerated by grouse-shooters and the farmers, and the country is not rough enough to give it sanctuary. But in Invermark Forest at the head of the Angus Glens the eagle is given protection. One might say that the red deer have gone from the forests of Clunie and Alyth, and so they have as full residents. This, however, is a frontier zone by our definition, and in winter and hard weather the stags come down the long glens of Glen Isla, Glen Fernait and Atholl. It is in this zone that there is so much outcry against the deer, which become such predatory bands on young corn crops, fields of turnips and potato clamps. A fair amount of coniferous timber is grown in this northeastern area of the frontier zone because the climate is fairly dry and the drainage good.
Dunkeld is one of the gateways to the Highlands proper, at the foot of Strathtay. From Dunkeld to Pitlochry we are in a valley made famous by an earlier Duke of Atholl in his zeal for planting. Larch became one of our most important conifers after the Duke had planted it so extensively during the 18th century. It is interesting to note, also, that it is in this afforested country that the new hybrid between the European and Japanese larch has occurred by a fortunate accident. The hybrid, with its hardiness and immunities, is expected to be a notable forester’s tree in the future. All this area and that already described carries a big stock of roe deer. Despite its unpopularity with the forester, the roe happily persists, apparently as strong as ever.
West of Dunkeld we are into Strath Bran, still timber country, grouse moors and rearing farms. The fauna of Highland hills are constantly pressing down into this zone and are as surely being scotched before the plain of Strathmore is reached. Peregrine falcons, wild cats, eagles, foxes, red deer—all these come through and rarely return. There are no high tops in this area until the head of Glen Almond where the summit of Ben Chonzie, 3,048 feet, dominates everything else in the district; yet there is big country here which the relative smoothness of the hill faces tends to emphasize. The streams have good brown trout and the valleys are always well wooded among the numerous farms. The bird population is rich and varied.
West again, we come into the Forest of Glenartney with its two sharp peaks of Ben Vorlich, 3,224 feet, and Stuc a’ Chroin, 3,189 feet, which are visible from Arthur’s Seat, Edinburgh. Glenartney is the most southerly of the deer forests proper, and though the high country of the two peaks is very suitable for deer, the winter trek of the animals makes the forest harder and harder to maintain in an age when the voice of agriculture is clamant.
The country now is getting much wilder and the easily walked slopes of good heather are giving way to some bare rock faces, to wetter sedgy hills and birch woods rather than conifers. Such is the country either side of Loch Lubnaig where the Forestry Commission is changing the face of the hillsides. The varied scheme of plantings here can serve as a model to confound those who hold that forestry spoils scenery. The same kind of country exists in the Trossachs round Loch Katrine of tourist fame. A Highlander hesitates to call the Trossachs Highland but there is no doubt of the beauty of the scenery. Birch and oak woods line the shore of the loch and hold a good number of black grouse still.
We now come to Loch Lomond, beginning at the foot of Glen Falloch as a narrow and quite uninteresting loch. It becomes more impressive the farther south we go down its twenty-odd miles. The shores are fringed with birches and oaks, and on the west bank particularly there are some fine groups of deciduous trees. Spring and autumn in this region have a charm beyond that of many Highland areas—and autumn, be it known, is a time when Scotland is at her most magnificent. If Ben Lomond looks splendid seen across the loch from Tarbet or Luss, a still finer view can be obtained from the other side where there is no road except the transverse one from Loch Katrine to Inversnaid Lodge, which can be reached also from Aberfoyle. The view westwards from above Inversnaid includes a group of “Munros”
(#litres_trial_promo) draining to Loch Sloy—Ben Vorlich (another of the name) with its two peaks, and Ben Vane and Ben Ime. This is the scene of a hydro-electric project and a road is to be made into the area which will certainly allow more people to see the fine scenery than have been able heretofore. This group of hills is in the West of Scotland fair and square and has a high rainfall. The most southerly of the group is Ben Arthur (the Cobbler), 2,891 feet, where there is much bare rock and excellent climbing. At the foot of the sedgy slopes of this hill we are on the west coast at the head of Loch Long. The role of frontier zone is practically lost here, for there is not the rich agricultural land immediately to the south. There is water, and, as the foot of Loch Lomond is reached, the industrial area which is but an extension of Glasgow.
Glasgow is fortunate in its landowners to the north. On both sides of Loch Lomond fair access is given to all, and every attempt is made to preserve the natural woodland and the forest fauna. The Loch Lomond-Trossachs area has priority as a projected national park area. The area would link up with the National Forest Park already established by the Forestry Commission west of Arrochar, and which now includes the privately-given peninsula between Loch Goil and Loch Long. This extremely broken stretch of Highland country, ironically called Argyll’s Bowling Green, is within a few miles of the busy industrial Clyde. The establishment of a national park, and the faithful implementation of the Town and Country Planning Act which is now in force in Scotland, should ensure to Glasgow an area of pristine beauty with a rich natural history, much of which yet awaits patient investigation.
THE CENTRAL HIGHLAND ZONE
This area gives the nearest approach to continental and alpine conditions that we have in Scotland. The southern boundary may be made a line drawn from Lochnagar to the head of Loch Lomond, including the high hills on the north side of Loch Tay. The western boundary would be a line from Loch Lomond through Ben Nevis to Carn Eige and Mam Soul, thence almost due east across the Great Glen at a point just south of Urquhart Castle. This northern line would continue from that point to Tomintoul, one of the highest inhabited villages in Scotland, at 1,280 feet; and the line from Tomintoul to Lochnagar could well form the short eastern boundary. The south-western and north-western corners of this arbitrarily delimited zone are the least typical, in that they lose the plateau-like quality of the Central Highlands proper, but on reflection I should not like to include the peaks round the head of Glen Lyon in the West Highland zone, nor do I think the triangle of country north of the Great Glen may rightly be said to have the sub-arctic-heath complex of vegetation like that of the Northern Highlands. Between 80 and 90 per cent of the ground in this central zone is above the 1,000-foot contour. Arable farming is scarcely practised except in the narrow straths. The farms of Glen Moriston constitute one of the incongruities of the north-western corner of our area, much more so than those of Cromdale and Boat of Garten on the northern edge east of the Spey, for these latter are typical upland farms. The slopes of the hills are mainly of good heather and after 2,500 feet become alpine desert.
The Central Highland zone has its particular interest for naturalists who may be specialists in some branches. There is the botanical field of the high tops, among which Ben Lawers, 3,984 feet, has always held a special place. The schistose of which this hill is composed breaks down easily, and there are exposures of other rocks as well, providing soil which allows a greater variety of alpine plants to grow than on some other summits. The richness of Ben Lawers is also due, probably, to the likelihood of the summit escaping the last glaciation.
The Cairngorm region is of special interest to ornithologists wishing to study the snow bunting and dotterel. The ptarmigan (Plate XVIIb) is common there and the golden eagle (Plate XIIIa) enjoys practical sanctuary, for even sheep-farming is absent from much of the area. The Cairngorm tops are our most considerable arctic relic. The ancient pine forests at the eastern and north-western foot of the Cairngorms are also a relic of a past age and contain the Scottish crested tit (Plate XV) and the Scottish crossbill. The entomologist also finds these forests of special interest. The central Highland area contains some of the biggest deer forests in Scotland, such as Blackmount in Breadalbane of over 80,000 acres (Pl. XV, p. 108), the Forest of Mar, which is almost as large, and the wonderful deer country between Loch Ericht and Loch Laggan, which includes Ben Alder, 3,757 feet.
Our central zone holds the upper reaches of three large river systems—the Dee which flows eastwards from the Cairngorms and the Grampians; the Spey which rises from tiny Loch Spey in the Corrieyairick Forest north of the high top of Creag Meagaidh above Loch Laggan; and the Rivers Garry, Tummel and Tay flowing southwards, joining and continuing as the Tay outside the central alpine zone. The much shorter River Spean which flows westward from Loch Laggan has now disappeared because of the erection of a hydro-electric dam and aqueducts at the foot of Loch Laggan. The Spey, rising at 1,142 feet on the backbone of Scotland, runs 120 miles in a north-easterly direction to the sea in the Moray Firth. It gathers its waters from the Monaliadh hills, from the Grampians and the Cairngorms, the largest area of long-snow-lying country in the Highlands. The River Truim, the Spey’s first large tributary, runs through Badenoch, one of the barest parts of the Highlands. It rises near the Pass of Drumochter, 1,500 feet, which takes the main road from Perth to Inverness. Badenoch has the appearance of a devastated countryside; an appearance partly due to nature and partly to the destructive hand of man several hundred years ago. This area was fought over many a time and bands of broken men were burnt out of their retreats just as the last wolves were a century or two later. The rock is a dull grey and apt to break down into a shaley scree. To my mind, the Forests of Drumochter and Gaick, a little to the east, are the most depressing part of the Highlands. The hills are big humps without individuality, there are screes but not fine cliff faces, and trees are few and far between. Even the weather has a habit of being leaden. The practice of burning heather is always obvious in that no hill face seems to bear an unbroken dark green surface of untouched heather.
West of the road, in the upper Spey Valley region and south of Loch Laggan, the hills become sharper and more shapely and there is a good deal of natural birch, among which are many stands of coniferous timber which in no way spoil the landscape. The Spey and the Truim join above Newtonmore, and from there until the Spey leaves the central zone, the straths and the slopes to over 1,250 feet hold large stands of planted coniferous timbers. There is still plenty of natural birch and juniper scrub as far as Aviemore and beyond. We are in a very beautiful area which is one of the most popular holiday resorts in Scotland for those who like quiet, a mixture of woodland and high hill and a sharp healthy climate of low summer rainfall. At Aviemore the Valley of the Spey widens, and if the observer climbs the wooded hillock of Craigellachie south-west of the village, he will see the old Scots pine forests of Rothiemurchus (Plate 16) and Glenmore as the floor of a great basin formed by the Cairngorms and the little range of hills to the north which culminates in Meall a’ Bhuachaille, 2,654 feet. Loch Morlich (Plate 2) lies in the middle of the basin and its bright sandy shores at the eastern end are visible. The dark green of the timber stretches through the pass or bealach at the foot of Meall a’ Bhuachaille into the Forest of Abernethy (Plate 17). The old trees have suffered more heavily here and have been replaced by plantations of Scots pine, but Abernethy is still beautiful and the birch and juniper take away the grim formality of the solid stands of planted timber.
The Cairngorms, which form the heart and the most extreme alpine conditions of our central zone, are fairly easily reached from Aviemore by means of the track and the pass known as the Lairig Ghru. The Lairig splits the granite massif of the Cairngorms into two halves at a height of 2,750 feet, and is the most spectacular part of the Cairngorms seen from Aviemore or farther west of the Spey. Ben Macdhui, 4,296 feet (Plate 20), is on the east side and Braeriach and Cairntoul on the west side of the pass. The summit of the Lairig is also the county boundary between Inverness-shire and Aberdeenshire. Just south of the summit are the very small lochans known as the Pools of Dee. The water is extremely clear and probably originates from springs. This is the source of the Dee which in twelve miles becomes a considerable river at the Chest of Dee. By time the Linn of Dee is reached (the uppermost limit of salmon in the river) we are into forest again, mostly planted Scots pine until we get below Braemar, where Ballochbuie still holds a fine show of the old pines. These are part of the Royal property at Balmoral.
The Grampian Hills south of the Cairngorms give a sense of vastness. Ben Iurtharn, 3,424 feet; Glas Thulachan, 3,445 feet; and the tops of Beinn a’ Ghlo, 3,671 feet; all these and many another 3,000-footer can be easily climbed on a pony, and once on those clean, smooth summits the pony can be let out to a gallop, so different are they from the sharp peaks, the broken ground and the boggy approaches to the high hills of the West. This country is remote from everywhere and since, once there, it is difficult to get lower than 1,500 feet, there is a great exhilaration in movement through these hills. The snow lies long up here but in summer there is a wealth of excellent grazing for deer, sheep and cattle. I have found patches of beautiful brown soil as high as 1,800 feet. One of the best routes into the Cairngorms is up Glen Tilt from Blair Atholl, past the Falls of Tarf. It is a long and arduous defile or U-shaped glacial valley for most of the way until the Bynack Shieling is reached at 1,500 feet. After that there is the sense of height and space, and the high hills of the Cairngorms lie ahead in a much more picturesque group than when seen from the west. This time it is the noble Glen Dee which splits the massif rather than the sharp nick of the Lairig Ghru. Trees are few up here, though the narrow dens which cut down to the Tarf from Fealar and round about have plenty of small birches, and curiously enough there are a few well-grown spruces at the Bynack Shieling; out of which spruces one day I frightened a capercaillie (Plate XIc). He must have come out of the wooded area of the Dee below Derry Lodge, where this bird is relatively common. The Forest of Mar was one of the places where the caper was reintroduced (unsuccessfully) in the early 19th century.
THE NORTHERN HIGHLANDS, A ZONE OF SUB-ARCTIC AFFINITIES
The northern end of Drum Albyn and its coasts becomes definitely a harder country north of Loch Carron than the West Highland Atlantic zone. The large island of Skye, set athwart the Minch, has an undoubted effect of checking the flow of warm water of the North Atlantic Drift. The coasts of the North-West have several long sea lochs, but the coast as a whole is tighter-knit than the islands and coasts of the Atlantic zone which fans out from the Firth of Lorne into the Atlantic Ocean.
The rocks of the northern zone on the western side are mostly very hard, and poor in such minerals as make good soil; they are Lewisian gneiss, Torridonian sandstone and quartzite; these three have little either of calcium or of fine particles which will become clay and contribute to the soil picture. Furthermore, where the bed rock itself is not showing through (and often it is over 50 per cent of the landscape) the ground is covered with peat which has no bottom of shell sand or clay which, on disintegration or removal of the peat, might become productive soil. Sand dunes occur on the coast at only a few places such as Gairloch, Gruinard Bay, Achnahaird on the north coast of the Coigach peninsula, across Rhu Stoer and at Achmelvich, and at Sandwood Bay a few miles south of Cape Wrath. None of these are of shell sand.
It is a hard, rocky coast to which a multitude of short, rapid rivers run from Drum Albyn—the Laxford from Loch Stack and Loch Mor into Loch Laxford; the Inver from Loch Assynt into Enard Bay; the Kirkaig out of the lochs below Suilven; the Polly, the Kannaird, the Broom and the Dundonnell Rivers; the superb Gruinard River which is only six miles long on its run from Loch na Sheallag; the Little Gruinard, even shorter, coming from the Fionn Loch which is one of the most famous trout lochs in the North; and the River Ewe, only two miles long after it leaves Loch Maree, but very broad; the Kerry River running into Gairloch, famed for its pearls; and the Applecross River which drains much of the peninsula of that name. Most of these rivers are noted for salmon and sea trout, though some are curiously poor. As things stand at the moment the rivers of this region, so variable in their flow from day to day, make up in economic value for the poverty of the land for agricultural and pastoral purposes and for general lack of timber.
The boreal or sub-arctic affinities of the northern zone are most marked on the two geological formations already named, the gneiss and the sandstone. Each rock has its very distinctive form and each contributes to what is probably the wildest scenery in Scotland except for the small area of the Cuillin Hills of Skye (Plate IIIa). But here in the interplay of gneiss, sandstone and quartzite the naturalist may walk for a week or more and see no human habitation other than an occasional stalker’s cottage. So rough and wild is the country that habitations unconnected with sport are difficult to find away from the sea’s edge. The outcrop of limestone in the Assynt district allows the exception of the crofting townships of Elphin and Cnockan to which allusion was made in the first chapter.
The Lewisian gneiss of the mainland rises to greater heights in the general run of the country than it does in the Hebrides, except in Harris and at one place in South Uist. Also, it is not hidden under such a blanket of peat as in Lewis. The gneiss country of Sutherland and Ross is one of a myriad little hills of great steepness, with little glens running hither and thither among them. The lochans are seemingly countless and most of them have a floor of peat. The gneiss hills themselves are like rock buns, looking as if they had risen in some giant oven and set into their rough shapes. This ground holds up the water in pockets in the rock and allows the formation of cotton sedge bogs and such very shallow lochans as grow water lobelia and water lilies. When these lochans are near the sea and grow reeds the bird life is rich. Greenshanks (Plate XIIb) are common in the gneiss country—say one pair to 3,000 acres, which is quite twice as many as may be found on the adjoining Torridonian sandstone. Heather (Calluna) is not common on the gneiss; the complex is one of dwarf willow, sedge and poor grasses. Also, this type of vegetation does not appreciably alter in the altitudinal range of the gneiss. For example, I could find no major difference in sample patches in the Gruinard Forest at the foot of Carn nam Buailtean at 600 feet, and at the top of Creag Mheall Mor in the Fisherfield Forest at over 2,000 feet. The hills maintain over all their mottled pattern of green and grey, and when the snow is on the tops there is never the distinctive line at about 1,750 feet which is commonly seen on the Torridonian formation.
The gneiss is difficult country to walk through: by keeping to the little glens it is impossible to steer a straight course for any distance and no one would attempt to go in a straight line over the hills. On the upper gneiss country where many detours are necessary round rock faces and soft spots, a speed of one mile an hour is quite good going. It is also quite easy to lose one’s self, for these little round hills are all very much alike.
The crofting townships on the gneiss are strictly coastal. Their arable grounds (Plate 7b) are usually tiny patches of an acre or less in the hollows or in the less steep faces of the rocks. Loch Laxford, a sea loch, shows some typical low gneiss country with crofts at Foindlemore and Fanagmore.
The gneiss tends to get higher the farther it goes inland. A’ Mhaighdean (the maiden) reaches 2,850 feet above the Dubh Loch in Ross, 10–12 miles from the sea as the crow flies. It forms a high cliff face on this hill of exceptional grandeur, a rare thing for the formation on the mainland. Its sea cliffs are nowhere impressive here because they are never sheer or higher than a couple of hundred feet. Even the Torridonian, a formation which one might expect to make magnificent cliffs, does not provide these in any quantity at the sea’s edge. The island of Handa, near Scourie and opposite Fanagmore at the mouth of Loch Laxford, is a splendid exception. The Torridonian rock is stratified horizontally, so the vertical breaks make nesting ledges for sea birds such as guillemots, razorbills and kittiwakes. There are sheer cliffs of nearly 400 feet on Handa, and in the little screes of earth among these, now covered with fescue and scurvy grass, there are large colonies of puffins and fulmar petrels. The white-tailed sea eagle nested on Handa until the second half of the 19th century. Handa is one of the few places on the Torridonian sandstone which provide true sea-bird cliffs. No other place on the formation can compare with it for numbers of auks, except perhaps Clo Mor, about four miles east of Cape Wrath, where there is a cliff of over 800 feet.
The splendour of the Torridonian is in the peaks it makes inland. Some are fantastic and others superb. There is only one Suilven and it is undoubtedly the most fantastic hill in Scotland (Plate 3b). It rises to 2,309 feet out of a rough sea of low gneiss. Seen from north and south it has a distinctive shape of a very steep frontal cliff and rounded top called Casteal Liath (the grey castle), then a dip and a lesser knob before a more gentle slope down to the east. But when seen from west or east the extreme thinness of the hill is apparent. Probably the Dolomites would be the nearest place where such an extraordinary shape of a hill could be seen. Suilven means the pillar which is a good name for the hill seen from the west. It is often likened to a sugar loaf, also. There are greyish-white quartzite boulders sprinkled on the top, yet there is a little alp of grass up there and an occasional bed of Rhacomitrium moss. The great terraces of Caisteal Liath itself are but thinly marked by such grasses and sedges as Festuca ovina forma vivipara and Luzula spicata as can send their roots far into the cracks.
One of the striking things about the Torridonian peaks of the far north-west is their isolation, caused by the vast denudation which has taken place, leaving these few hard cores of sedimentary rock overlying the wilderness of gneiss hillocks and innumerable lochans. The term hard core is here being used metaphorically and not geologically. North of Suilven and Loch Assynt is the massif of Quinag, five conical peaks capped with quartzite, with a fine rampart of cliff and scree on the west side, which is nearly three miles long. The massif is no higher than 2,653 feet, but how much more impressive is it than half a hundred three-thousand-footers in the Central Highlands! South of Suilven there is Cul Mor, 2,786 feet, surrounded on three sides by great precipices; and Stac Polly, 2,009 feet (Plate 4b and Plate 10) the narrow ridge of which is like one of those fairy castles of childhood tales perched on the top of steep slopes. Ben More Coigach rises to over 2,000 feet in under a mile from the sea as the crow flies. The air of this countryside with its lower rainfall is generally much clearer than farther south in the Highlands and adds to that sub-arctic quality which characterizes the area.
Before leaving this far northern corner, the ranges of Foinaven, 2,980 feet, and of Ben More Assynt, 3,273 feet, must be mentioned. The group culminating in Foinaven is without doubt the barest range in Scotland, and composed of that unyielding white rock, the Cambrian quartzite. The northern part is like a giant E, the crossbars being ridges peppered heavily with boulders which form screes again below the shoulders: the hollows of the E are fine corries on the slopes of which the snow bunting has bred. The southern part is a horseshoeshaped ridge of which Ben Arkle, 2,580 feet, is the western rampart. This hill of Cambrian quartzite with its banding of white scree may be viewed to perfection from the highroad on the shores of Loch Stack; but for the greatest glory of this range a six-mile trek must be made to reach the vast horseshoe corrie and Loch an Easain Uaine, the loch of the green falls. It is well to rest here awhile and realize that the pine marten is probably commoner in this neighbourhood than anywhere else in Britain, to remember the snow bunting up in the tumble of boulders and possibly see him feeding on the buds of Saxifraga oppositifolia. The alpine species of plant creep far down these bare hillsides and one wonders what there is here to recompense the deer for the energy used in attempting to graze these slopes. The boreal affinity of this range was further emphasized by the occurrence of alpine butterwort (Pinguicula alpina), which was found nowhere else in Britain but on the high tops of Sutherland and Ross; unfortunately this species may now be quite extinct, as it has not been found since 1900, according to Druce’s Comital Flora. The same authority puts 1794 as the last date on which this plant was found in Skye.
Ben More Assynt itself is a solid quartzite cap with igneous intrusions set upon a mass of Lewisian gneiss. There has been a series of geological overthrusts in the region, in which tumults areas of limestone have come to the surface. This limestone has affected the natural history of the whole region, causing a wealth of crustacean and other aquatic life on the waters affected by the limestone, differences in the temperature of the water of some streams which suddenly rise from the rock, allowing the formation of water-worn caves in which have gathered soil and bones of animals of earlier times. Such organic remains are rare in the Northern Highlands.
The comparatively low ground of all this northern region of the gneiss, so difficult of access and so plentifully strewn with lochs, is also a place where sub-arctic birch scrub (Plate IV) is common and there is a certain amount of hazel. There are large stretches of birch in Inverpolly Forest (Plate 4b) in the vicinity of Loch Sionnascaig, which is one of the most beautiful lochs in the whole Highlands. There are pristine birch-wooded islands in the loch where the grey lag goose bred not so long ago and where the pintail duck has bred recently. There is more birch round Lochinver and below the north face of Quinag, and many a stretch may be found on the hill far from the roads, in places which are almost unknown to the naturalist. Some day we may find the redwing building in these woods, for this bird has been heard singing here from time to time in April, and the redwing is essentially a native of the sub-arctic birch wood.
The eastern side of the extreme Northern Highlands is given up to extensive sheep-farming. The hills are of no great height and are of easy slope. The herbage is sweet and good. The largest sheep farms in Great Britain are here, some having upwards of 10,000 ewes. The breed kept is the Cheviot of the distinctive lustrous-woolled Sutherland type. The lambs are sold annually at the great sales at Lairg. No man was more responsible for the development of Cheviot sheep-farming in the North than Sir John Sinclair of Ulbster, in the 1790’s. The influence of sheep-farming on the natural history has been profound and will be given special attention in a later chapter.
This far northern area has been treated at some length, because it is the most remote part of the Highlands and one of which detailed studies in natural history have been rare. It may be recommended as an exhilarating and fruitful field for exploration.
South of Loch Broom, the Torridonian hills are more thickly grouped and reach their highest peaks. Their spiry form and the high corries facing to the east are distinctive. The quality of herbage is generally poor and the terraces formed in the lower reaches of the Torridonian hold up the heavy rainfall so that it is often quite impossible to get about dryshod. How different is the nature of the ground from those smooth dry slopes of glacial sand and gravel which are such a marked feature of the Central Highlands! The differences brought about in the vegetational complex have not been sufficiently stressed by plant ecologists in the past. The ground has not been well walked through and explored as yet.
There are two high hills of the Torridonian which have north-eastern corries quite the most magnificent of their kind and few who have seen them both can decide which is the better. This in itself should show how similar are such groups of hills and the forces which moulded them. I allude to An Teallach of Dundonnell (Plate IIIb and Plate 4a), 3,485 feet, and Beinn Eighe, 3,456 feet, between Kinlochewe and Loch Torridon. Each of these hills has three corries facing NNW. to NE. Coire Mhic Fearchair is the most westerly of the corries of Beinn Eighe, and the Toll Lochan corrie of An Teallach is the easterly one of the range. Some of the buttresses in Coire Mhic Fearchair are exceptionally fine and the corrie makes an almost perfect horseshoe, but for myself I think I prefer the Toll Lochan corrie, for the cliff face at the head of the lochan is of greater depth and of superb architecture, nearly 1,800 feet of it.
Between An Teallach and another corried Torridonian peak, Beinn Dearg Mor, 2,934 feet, is the broad amphitheatre known as Strath na Sheallag, at the head of Loch na Sheallag, from which the Gruinard River runs. This strath is beloved of the deer, and though so remote it draws cattle, sheep and ponies to it from far away. Just as An Teallach has Beinn Dearg Mor as an outlier, so has Beinn Eighe her Beinn Dearg, 2,995 feet, almost a replica of its cousin of Strath na Sheallag. Liathach, 3,456 feet, Beinn Alligin, 3,232 feet, and Slioch, 3,217 feet, these are just three more of these splendid Torridonian peaks—clear of peat from 1,750 feet upwards and often topped with a white cap of quartzite boulders. The sudden change from wet peat-laden terraces to the upper slopes of bare rock, or thin covering of brash and alpine vegetation, results in a sharp snow line in winter which gives these hills a special seasonal beauty. This sudden cessation of the peat immediately allows a different flora, one of plants which can withstand droughts and sudden changes of humidity, and which prefer sweeter conditions than are possible on peat. Here and there among the alpine poa grass and viviparous sheep’s fescue are straggling plants of dwarf juniper, clinging close to the rock. Sea pink and thyme are also to be found on the gravel. Eagle, peregrine falcon and wild cat abound in this country, and as it is all deer forest and not grouse moors of any consequence, the eagle is allowed more sanctuary than it has been given farther south and east.
The glens of the Torridonian area of the North are often well wooded. They have been owned by people with a fair (or perhaps unfair!) measure of worldly riches, who have been able to spend a good deal of money on planting for amenity. Take Dundonnell for example, at the head of Little Loch Broom: the loch side is bare of trees and is given up to crofting townships, but soon after the head of the loch is reached one is into a fine wooded glen. There are a few hundred acres of Scots pine of greatly varying density stretching up the southern side to an altitude of 1,000 feet. There are alders, oaks, rowans, and hazels along the river bank, and some hundreds of acres of birch at the head of the glen reaching up to 1,500 feet. But all round the cultivated strath and the house which was built in 1769 there are signs of planting for beauty: limes, many fine beeches, sycamores, ashes, elms, oaks, chestnuts and big old geans; and until a few years ago there were many acres of fine larches on the north side. The wild life of such a glen is obviously profuse and varied. We have these men of a past age to thank for planting that which we now enjoy, just as we may blame those of a century earlier who were denuding the Highlands of timber.
Loch Maree is another place where there are some very fine woods, but here the sub-arctic quality of the northern zone is being lost and replaced by the complex of sub-alpine vegetation. Near where the Ewe River from Loch Maree goes into the sea in Loch Ewe there is a famous garden which grows a great variety of rhododendrons and azaleas and many sub-tropical plants and plants from Oceania. This is just another facet of the Highland paradox, the garden at Inverewe lying between the stark precipices of Ben Airidh Charr and the bare windswept slabs of Greenstone Point where the sea is never still. And if I may add one more touch of paradox, I saw a kingfisher on the rocks at Greenstone Point at the edge of the tide, one September day.
CHAPTER 3 (#ulink_31808313-a35d-5317-a253-4380d442e1aa)
RELIEF AND SCENERY (continued)
THE WESTERN HIGHLANDS OR ATLANTIC ZONE
SOUTH of Skye the coasts of the West Highlands fan out much more than to the north of that island. Indeed, there are several considerable islands reaching out into the Atlantic. The Outer Hebrides are not masking the influence of the Atlantic on this area as they do on the north coast of Skye. The influence of the Atlantic Ocean on this zone is both direct and inhibitory, and indirect and encouraging to a wealth of plant growth. The island of Islay, for example, changes character completely between its western and eastern halves. On the Atlantic side there is the lack of trees and shrubs and the presence of short sweet herbage salted by the spray from innumerable south-westerly gales, whereas there are beautiful gardens, palm trees and some forestry on the south and east sides. The Rhinns of Islay on the Atlantic coast are not heavily covered with peat as is a good deal of the eastern half. Islay is an island of many good arable farms, and it has several square miles of limestone country.
The waters of the North Atlantic Drift cast up on these Atlantic shores pieces of wood and beans of West Indian origin, and plants such as the pale butterwort (Pinguicula lusitanica), pygmy rush (Juncus pygmaeus) and the moss Myurium Hebridorum which occur again on British coasts only in the south-west, here turn up in fair numbers. The pale butterwort occurs in the bogs of Portugal and western Spain, and on the west coast of France; Myurium moss is found in the Azores, the Canaries and St. Helena as well as in our Outer Isles. Dwarf cicendia (Cicendia pusilla) has also turned up in this zone, though previously found in the British Isles only in the Channel Islands. More recently, Campbell and Wilmott (1946) have found another Lusitanian plant in Stornoway Castle park, namely Sibthorpia europaea. The work of Professor Heslop Harrison and his group from the University of Durham should be consulted. It is his opinion that these western cliff edges escaped the last glaciation and thus their Pleistocene flora was not exterminated. Others hold that the flora must have been introduced since then.
Jura is not so well served with the rich quality of vegetation we may find in Islay or even in small Colonsay and in Mull. It is composed of quartzite, which is poor stuff. Jura is also heavily covered with peat and suffers in consequence. A thick blanket of peat has a very great depressing effect on the variety of vegetation and in limiting the growth of deciduous trees. Jura is an island of high hills. The Paps rise to 2,571 feet and are quite rough going. It was on these hills that Dr. Walker of Edinburgh in 1812 conducted his classic experiment on the differential boiling-point of water at sea level and at the top of the Paps. Jura has a very small population of human beings on its nearly 90,000 acres. The island is so poor that its long history of being a deer forest will probably continue. In mythological literature Jura appears as being uninhabited and a place where heroes went a-hunting. It was on Jura during the latter part of the 19th century that Henry Evans conducted careful studies on the red deer. His were the first researches of a scientific character on Scottish red deer, yet he never set out to be more than a scientific amateur.
The island of Scarba, of about 4,500 acres, high and rocky, lies north of Jura. The Gulf of Corrievreckan is in the narrow sound between the two islands. This celebrated whirlpool and overfalls is caused by the strong tide from the Atlantic being funnelled through a strait, the floor of which is extremely uneven. The sound is quiet at the slack of the tide but is dangerous to small craft when the tide is running. The largest whirlpool is on the Scarba side of the sound, but there is a spectacular backwash on to the Jura coast which used to be reckoned very dangerous in the days of sailing boats. The maximum current is probably about 8
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knots which is very fast for a large bulk of water. No herring drifter or ordinary motor fishing-boat could hope to make headway against such a current, for their maximum speed in calm water is not more than 10 knots.
This West Highland zone has what the North Minch lacks, a number of sizable islands which are not big enough to lose their oceanic quality, and not so small that they are utterly windswept. The islands of Colonsay and Oronsay, west of Jura, are an excellent example of islands which have the best of almost all worlds. Naturalists may be glad that Colonsay is in the possession of one who recognizes its value and beauty in the natural history of the West. Most of the island is of Torridonian sandstone of a different complex from that farther north, but there are overlays here and there of limestone and its derivative soil, and the 100-foot beaches are another place of good soil. There are sand dunes, cliffs and rocky beaches where several rare maritime plants are to be found. There are fresh-water lochs with water lilies and the royal fern in profusion. Natural woods of birch, oak, aspen, rowan, hazel, willow and holly also occur, and beech has been planted. The sight of these, so near the Atlantic and its gales, may be imagined from this short passage from Loder’s exhaustive book:
“The woods are being rejuvenated by young plantations of Birch and Aspen, which are springing up naturally and contending for supremacy with an annual luxuriant growth of bracken. The Woodbine twines over the trees, and festoons along the edges of the numerous rocky gullies that cut up these slopes. Ivy has climbed up and formed pretty evergreens of the more stunted of the forest trees. The Prickly-Toothed Buckler Fern grows in profusion, and the little Filmy Fern is also to be seen under mossy banks.”
There has been considerable planting of coniferous and deciduous trees for amenity in this Atlantic island so that it now presents a luxuriant and well-wooded aspect in the neighbourhood of the house. But in gazing on these woods now and noting Colonsay’s wealth of small birds, we should remember the effort entailed in beginning to establish these conditions. Loder says:
“When planting in the island first began, the trees made so little headway that it was considered amply satisfactory if they formed good cover. For the first ten years or so they made little progress, and many places had to be planted over and over again. Protection from animals and weather was provided in the first instance by dry-stone dykes, 5 feet high. Alder and Sea Buckthorn were planted along the most exposed edges. Alders and various species of Poplar were used in wet situations but the poplars did not last well, and were liable to be blown over. It was only as the trees made shelter for each other that they began to show any vigorous growth. Indigenous species such as Birch, Oak and Rowan, have sprung up on hilly ground where the planted trees failed to establish themselves.”
The trunks of trees in these Atlantic places tend to become covered with lichens such as Parmelia perlata and Usnea barbata, and mosses such as Eurhynchium myosucoides (on birch), Ulota phyllantha, Hypnum cupressiforme and Brachythecium rutabulum. These trees seem to be much more affected by the humid climate than such exotics as Escallonia, Ceanothus, Verbena and Mimosa (Acacia) which grow luxuriantly. This is one aspect of Colonsay, but there are also its sedgy and heathery moors like those of many another island of the West, and at the southern tip, where the Atlantic has full play over the Torridonian and mudstone slabs gently rising from the sea to make platforms and pools near the tide level, the Atlantic grey seal breeds in fair numbers. Elsewhere, on the cliffs, kittiwakes, razorbills and guillemots breed; and there are three species of tern, arctic, common and little, breeding on the island.
Colonsay and Oronsay together might well be looked upon as an epitome of the West Highland world in its full range and consequences of Atlantic exposure and sheltered mildness.
Farther to the north-west are Coll and Tiree, two more islands which receive practically the full force of the Atlantic, but which show decided differences in natural history. Tiree is very low indeed. The rocky portion of the island, of Lewisian gneiss, reaches its highest point in Ben Hynish, 460 feet, but by far the greater part of Tiree (Plate 25) is but a few feet above sea level and composed of blown shell sand resting on a platform of gneiss. The island is one of good-sized arable crofts and is so far different from most West Highland districts that it has a Clydesdale horse-breeding society of its own. The sandy pastures of Tiree are deficient in cobalt but recent researches in mineral nutrition of animals have allowed the farmers of Tiree to dress the land with as little as 2 lbs. an acre of a cobalt salt and prevent the onset of pine in sheep. The island has particular interest for the birdwatcher: first, it is on a migration route and gets both summer and winter visitors which would not be seen anywhere in the North Minch, and its rich arable land also attracts a large number and variety of birds. Loch Vasapol of Tiree is a famous place for various duck. Tufted duck breed there and the gadwall is found there in winter though so uncommon elsewhere in the West. The vast beaches encourage certain waders, including the bar-tailed godwit, sanderling and greenshank. In the past the snipe-shooting was reckoned the best in Europe. Happily, there is less of it now.
Glacial action in Tiree is shown by the Ringing Stone, a huge rounded boulder of augite which probably came to rest there after a journey in the ice from Rum. The stone is marked by many ringed hollows on its surface.
The island of Coll, once one is within it, reminds one of the low gneiss country of Sutherland. Here the innumerable little hills are still smaller than in Sutherland and not so steep, none rising above 339 feet. The island presents a uniform rocky appearance when seen from a distance on the east side. On the west side of Coll are miles of shell-sand dunes, a feature which tends to be characteristic of many of the islands which meet the full force of the Atlantic and are low enough to have allowed the sand preliminary lodgment. The interior of Coll is just peat where it is not bare gneiss, yet with its western pastures it has always had the reputation of being a good place for cheese and sound dairy cattle. This island is important for the student, of distribution of plants in relation to the last glaciation and associated changed ocean levels.
The low, sandy islet of Gunna lies between Coll and Tiree. It is a great place for Sandwich, common and arctic terns and I believe the little tern nests there too. Such burrowers as the sheld-duck are plentiful, of course. Barnacle and grey lag geese are common in winter.
The small group of tertiary basalt islands known as the Treshnish Isles lie between Coll and Mull. The most southerly one has a rounded cone of an old volcano, 284 feet high, which gives the island the name of Dutchman’s Cap (Plate Va). The middle island of the group, Lunga, also has a volcanic mound rising to 337 feet, but the other small islands are all flat-topped with sheer sides of amorphous basalt resting on a platform of lava. This platform is of great importance in the natural history of the Inner Hebrides because it makes a breeding ground for the Atlantic grey seal. The Treshnish group, especially the Harp Rock of Lunga (Plate XIXa), is a nesting place of kittiwakes and auks and fulmars. Storm petrels nest in the Treshnish also, and the Manx shearwater on Lunga at least. The quality of grass on these islands is excellent and attracts a vast flock of barnacle geese in winter. The green rich grass of the islands is reflected again in the presence of large mixed flocks of starlings and peewits. In winter-time hundreds of blackbirds and a good many thrushes live on the Treshnish group. Lunga, being infested with thousands of rabbits, has a stock of seven buzzards.
The Cruachan of Lunga will be a good place to rest for a few moments and look at the topography of Mull, that very interesting member of the Inner Hebrides, Mull of the Mountains as the Gael calls it. The eye is first struck by the shapely peak of Ben More, 3,169 feet. This is the highest point reached by the tertiary basalt in Scotland. The cone itself is the result of great weathering, and the various beds of this amorphous lava are evident now in the truncated edges of the lower slopes of the hill. For sheer hard going, the descent from the summit to Loch Scridain takes a lot of beating, for the traveller is constantly having to make his way round these faces of rock which are not readily obvious to him as he comes down the hill. The terraced quality of Mull is obvious in a large part of Loch Scridain, the terraces being exactly the same height on either side. The peninsula between Loch Scridain and Loch na Keal reaches on the north side a stretch of some miles of very fine cliffs with sweeping talus slopes at their foot. The cliffs of Balmeanach are to my mind one of the striking features of Mull. The 1,600-foot basalt cliffs have trapped the cretaceous sandstone layer beneath them. The cretaceous sandstone—the local representative of the chalk—may be found in a narrow stratum just above sea level. These cliffs are difficult to explore and remain largely unexplored. Down below, the small island of Inchkenneth, the burial place of old Scottish kings and chieftains, is also composed of low strata of this cretaceous sandstone. If there is anywhere where chimneys must have cowls it is on Inchkenneth, for the down draughts from the great cliffs in a south wind are tremendous. Slates have to be specially cemented on the roofs. Corn and hay stacks suffer badly in this abnormal situation.
The whole of the north end of Mull consists of green even terraces with occasional gullies. The islands of Ulva and Gometra are similarly terraced flat cones with occasional gullies. The ground is porous and does not form basins for freshwater lochs; peat is absent. Bracken grows rampant here; indeed, Ulva is almost a museum piece for showing what luxuriant growth bracken can make in the Highlands. On the terraces, only the tips of the horns of Highland cattle can be seen above the fronds, but in the gullies the bracken tries to reach the same height as the plants on the terraces and may grow to a height of 12–15 feet. Trees of many kinds grow well in the sheltered parts of Mull on this soil from the volcanic rock. Just as trees were impossible on the tertiary basalt cliffs of Balmeanach and on Inchkenneth, they reach extraordinary luxuriance and beauty where the calcareous cretaceous sandstone appears again round the edge of Carsaig Bay on the south coast of Mull. This pocket will well repay a visit from the botanist and, I should imagine, from the entomologist. The cliffs to the west of Carsaig are by no means as impressive as at Gribun, but in their face there is to be seen a fine fossil tree fern first brought to the notice of geologists and naturalists by Dr. Macculloch in the early 19th century (Macculloch, 1824). Delicately coloured crystals are also to be found in these cliffs of the south coast.
The south-east end of Mull is dominated by bosses of gabbro called Sgurr Bhuidhe and Creach Bheinn (2,352 and 2,344 feet). From them we may look down on the north side to the long, bare, impressive valley of Glen More and on the south to the tree-lined waters of Loch Uisge and Loch Spelve. The southern peninsula of Laggan, formed by Loch Buie and Loch Spelve and almost made an island by Loch Uisge, reaches nowhere to more than 1,250 feet, but it is extremely rough and rocky, with plenty of scrub birch. Few people have walked through that ground which for many years now has been kept as a small and very private deer forest of 5,000 acres.
The islands of Muck and Canna are both of tertiary basalt on an erosion platform at tide level of lava that looks like clinker. Their soil is so good and their position in the Atlantic so favoured that these islands can grow what are probably the earliest potatoes in Scotland, i.e., May 31. The sheep of these islands do extremely well and come to the mainland in such good order that mainland buyers are hesitant to buy the lambs because they know they have nothing so good to offer them to keep them growing. The wealth of species of insects, molluscs and other invertebrates on these tertiary basalt islands is much greater than would be found on those of the Torridonian or gneiss formations, even though the basalt does not tend to allow lochans to form. The Glasgow University Expedition to Canna in 1936 published a full report of their extensive finds. Muck and Canna both offer the right kind of cliffs for sea birds, and Canna is also a breeding station for the Manx shearwater.
The island of Eigg (Plate 5) is a big shearwater station, the birds nesting well up towards the Sgurr, 1,280 feet. The Sgurr is the most obvious physical feature of Eigg and by far the island’s most interesting natural phenomenon. It is a geological curiosity which has shed light on the geology of other areas far distant. The late Sir Archibald Geikie solved the riddle which Hugh Miller answered unknowingly at an earlier date. The Sgurr itself is of pitchstone, resting on a thin river bed of conglomerate which contains fossil pieces of driftwood from some far distant time. Beneath this is the tertiary basalt again. The pitchstone shows columnar jointing in places, a character which is still more strongly marked on Oidhsgeir, 18 miles away to WNW. This low islet of pitchstone is considered to be part of the same sheet as the Sgurr of Eigg. There is one other feature of Eigg deriving from its geology which should be mentioned here—the musical sands of Camus Sgiotag, a small bay on the north side of the island. These sands are of partially rounded quartz grains of similar size. If the sand is dry a shrill sound is heard as one walks over it.
To return for a moment to the few acres of Oidhsgeir, an islet which does not reach higher than 38 feet above sea level. Here on the top of the pitchstone columns which are 8 inches or so across the top are found the nests of kittiwakes in the season. There are also great numbers of common and arctic terns and eider ducks. Harvie-Brown, visiting the islet several times in the ’80’s and early ’90’s of last century found teal breeding and was convinced that the pintail duck had nested there also. This phenomenon of a small islet in the open sea gathering to it an immense number of living things for the purpose of their reproduction is one to which we shall return in a later chapter on the oceanic island. The deep-cut channels among the pitchstone columns are also a playground for the Atlantic seal. One channel on the south side runs up into a pool where a boat may lie in perfect safety. Many are the occasions when lobster fishers and venturers in small boats have been glad of the quiet pool of Oidhsgeir. What a strange feeling it is to be lying snug in such a place with the mighty ocean pounding but a few yards away and the spray flying over!
The island of Rum, with its three rock types of gabbro, Torridonian and granite, is for the most part a closed book to naturalists. We may hope this unfortunate period of its history is drawing to a close and that it may yet have a future as a priceless wild-life reserve. There are red deer and wild cats on Rum, there are otters round the shores and on the burns, and such species as badgers and roe deer could be introduced if introductions were thought desirable. Some of the finest kittiwake cliffs in the kingdom are to be seen on Rum, and the Manx shearwater nests in holes high up the 2,600-foot hills. The golden eagle is there still, though the sea eagle disappeared during the second half of the 19th century. Given the chance, we may expect the chough to return to Rum.
Skye may be looked upon as the northern outpost of the Lusitanian zone. It has suffered human depopulation like many another Highland area, but Skye is still one of the most heavily crofted areas of the West. Preservation of game has practically ceased and almost all the hill ground is now crofters’ grazing. Topographically, Skye is magnificent, with its Cuillins and its Quirang, but from the point of view of wild life it is somewhat disappointing. The whole area facing the Minch is faunistically poor, as was pointed out by Harvie-Brown fifty years ago.
The island of Raasay, however, between Skye and the mainland, has a surprisingly rich variety of small birds, doubtless as a result of the woods and the large amount of park-like ground which is of Liassic origin. Personally, I should say that the Lepidoptera of Skye and Raasay would repay close scrutiny, not only from the point of view of numbers of species, but from the areas of distribution. Heslop Harrison and his group have already made fruitful researches in this direction. Raasay, like Mull, has its own sub-species of bank vole (Clethrionomys = Evotymys).
The islands of the Atlantic zone are by far the most interesting part. The mainland coasts are often hidden and tend to lose character. But the country bordering the long sea lochs is of exceptional beauty and contains some habitats—such as the indigenous oak woods—which are almost unique in Scottish natural history. To walk the length of Loch Sunart, ten miles out of the twenty through these oak woods, in the fine weather of June is an aesthetic experience, if only for the sight of the redstarts which are here in great numbers. The scenery of the distance is as beautiful as the redstart among the oaks and hazels near at hand. Perhaps the better way is to travel eastwards from Kilchoan and Ardnamurchan Point where the quality of ocean is apparent as on the islands. Sanna Bay on the northward tip of Ardnamurchan is one of the most beautiful shell-sand bays of the West, but it is rarely visited because of its remoteness. East of Glenborrodale the sense of sea is lost and we are in the woods with the loch below us. The peak of Ben Resipol, 2,777 feet, dominates the landscape and is most shapely when seen from this airt. The traveller can hardly miss seeing Ben Iadain, 1,873 feet, and on the other side of the loch in Morvern. It is a little cap of tertiary basalt perched on the Moine schist, but between the two is a very narrow band of chalk. The sight of this little hill cannot fail to impress one with the immense amount of denudation which must have taken place to remove this molten layer of amorphous volcanic rock from so much of this countryside.
Though the oceanic birds such as kittiwakes and auks are lost as one moves up these long sea lochs, it is surprising how many sea birds are to be found breeding in the season. Arctic terns, eider ducks, herring gulls and mergansers—all are here in numbers. And where there are shallow shores and estuaries there are parties of curlews, oystercatchers and ringed plovers. The hillsides above these long sea lochs are almost devoid of heather. The vegetational complex is one of various species of sedge, a few grasses such as flying bent and mat grass, and bog myrtle and deer’s hair sedge. Heather will appear at the edge of a gulley perhaps where the drainage is good. From a distance the most obvious plant may be bracken—great sheets of it, darker green in summer than the herbage and red in winter.
The ecology of the long sea lochs and their intertidal zones is a subject of great interest for those who have the techniques to follow such studies. The gradual increase in salinity from head to foot of the loch, the diurnal variation caused by the tide, the spasmodic variations caused by spates and droughts, the currents formed, and their effects on the life of the waters, still remain to be worked out in detail. Space will not allow of individual description of all the narrow and long sea lochs from Loch Fyne to Loch Alsh: each one has its similarities and distinctions, and certainly each should be visited by the naturalist who is also keen on good country. Most of these narrow lochs have high hills rising from their shores, which means that their south side loses the sun for four months in late autumn and winter. Loch Hourn is particularly sombre in winter because the hills of Knoydart, which reach to 3,343 feet, seem to tower above the loch. Loch Nevis, on the other hand, is sheltered from the north by these same hills, and the North Morar hills to the south of this wider loch do not rise above 1,480 feet. Inverie, therefore, in its sheltered bay on the north side of Loch Nevis, is one of the kindest places in the West Highlands, despite the high rainfall. Indeed, the West Coast is full of these pockets of kindly shelter allowing luxuriant growth. Many of the policies of the large houses have magnificent specimen trees which have grown within a hundred years or so to a size which would have been impossible in a large part of England.
When these sea lochs narrow at their mouth there is a diurnal tide race of considerable force. That at the Corran Narrows of Loch Linnhe runs at 8 knots at ebb and flow, but that at Connel Ferry on Loch Etive is very much more than this and is quite impassable at half tide. When the tide begins to flow here there is the extraordinary sight of a waterfall in reverse, made by the inrush of sea water.
This section may be concluded with mention of the fine piece of country round the shores of Loch Etive (Plate Vb) and up to Glen Coe (Plate 6). Ben Cruachan, 3,680 feet, is one of the landmarks of the Highlands. Cruachan and Ben Starav, 3,541 feet, are of granite and lie either side of Glen Kinglass which runs from the east bank of Loch Etive. There is happily no road through this glen and it is therefore almost untouched. The sides are lightly wooded; the river is of that clarity which is common in waters coming off granite, and as one climbs past the trees and by numerous falls the Forest of Blackmount is reached. This great high place has lost all western character which was expressed at the foot of Glen Kinglass. Blackmount has always been deer forest. Its swan song is that charming book by the late Marchioness of Breadalbane, The High Tops of Blackmount. You may object to all that this great lady stood for, but if you have a fine taste for country and appreciate writing which conveys the atmosphere of particular country you should read her book.
If one makes a cross-country trek from the heart of Blackmount to the head of Glen Etive, a country of high, spiry peaks is reached. What is more, it belongs to the nation. The Royal Forest of Dalness, Buachaille Etive, Bidean nam Bian, and some of the best climbing ground in Scotland is included, and it is probable that adjacent areas will also come under state ownership before long. The botanical and geological interest of the area is considerable, but the student of animal life will find it rather bare. Once more, at the head of Glen Coe we are on the border of our zone. As we look eastwards across the dreich Moor of Rannoch (Plate VIa) it is into Central Highland country.
THE OUTER HEBRIDES OR OCEANIC ZONE
This is the most westerly portion of Scotland, the seventh degree of West Longitude passing down through the middle of this long range of islands which effectually shields the northern half of the West Highland coast. If we study a population map we see that the greater part of the people on the Long Island, as the whole group is called, are fairly densely packed on to the western fringe. Some more dense places are also found on the extreme east of Lewis, as on the Eye Peninsula or Point as it is always called in Lewis. By merely looking at a map one might ask why the people are so densely grouped on the west side where harbours are fewer and where the force of the Atlantic Ocean is unbroken. The very fact of human density of population is surprising to anybody accustomed to the alarming rate of depopulation on the mainland shore of the West Highlands. The Hebridean has a love of home which is unconquerable. There he has remained through thick and thin, sticking to his fringe which is between the mighty ocean and the deadening peat bog of the interior.
The half-million and more acres of the Outer Isles mean nothing in relation to the human population which lives there because to a large extent the interior is just as uninhabitable as the ocean. The people being confined to the coastal fringe live what might be called an open urban existence without town planning.
The overpowering reason for the human species being confined to this fringe is that here the awful blanket of peat ends and the ocean has thrown up an immense weight of shell sand. As the dunes have stabilized through the millennia and the stiff marram grass has given way to kinder herbage, a light lime-rich soil has formed. There are miles and miles of the white sand on the Atlantic shore, and above it the undulating machair (Plate XIXb) of sweet grass on which are reared great numbers of Highland and cross cattle. Flocks of barnacle geese come to the machair in winter and add to the humus content of the sandy soil. The prevailing south-westerlies continue to blow winter and summer, year after year, century after century. The tangle from the shallows of the ocean, the various Laminarias of the marine botanist, is torn from its bed and washed up on the beaches. Man comes down with his ponies and carts and creels and takes up some of it to spread on ploughed portions of the machair. All these things are helping to make soil, and the sand itself in these gales, especially if the winds are dry, is being blown up towards the blanket of peat which overlies the archaean gneiss of the Hebrides. The sand sweetens the peat, causes its barren organic matter to be unlocked and become fruitful of herbage for man’s beasts. Their dung still further ameliorates the peat. Such is the constant process, in which the storm is a necessary and beneficent factor in allowing and maintaining fertility. But once the coastal strip is crossed the peat reigns supreme. Its blanket must have increased about ten feet since early man came to the Outer Isles, for only the tops of the fine Megalithic stones at Callernish, Lewis, were showing when Sir James Mathieson of the Lews undertook their excavation. The landscape in the bog is shortly described—a low undulating plateau of peat, bare grey rock of gnarled shape, and thousands of small and large lochans of brown acid water. If we wander through these areas of peat we shall come upon drier knolls where the rock comes to the surface or is not far beneath, and here we shall find turf and greenness for a space. The shielings of Lewis have been and still are here. They are the summer dwellings of a pastoral people taking advantage, for their cattle and sheep, of the short spell when the peat grows its thin crop of sedge and drawmoss. The people lived on the little knolls as on islands, bringing their cattle up to them twice a day for the milking; throwing out their household waste—little that it was—and adding their own quota of dung and urine. The shieling life is mostly gone but the green knollies in the sea of rock and peat remain.
We may digress at this point to consider the nature of peat, this substance which covers a million and a half acres of the Highlands and Islands and the existence of which is a most important factor in the natural history of the area and of the scenery. A study of the peat is interesting not only for what it grows and harbours now, but for the history to be deduced from a deep profile of it. Peat forms under the influence of certain definite conditions and their consequences: the first requirements are high precipitation and a general coldness of atmosphere in the growing season sufficient to inhibit bacterial activity in the waterlogged soil, but not cold enough to prevent growth of certain plants. A vegetational complex of sour bog plants, such as sphagnum moss (Plate 22b), sedges of various kinds and cross-leaved heather, soon occupies the ground to the exclusion of all those plants which need a well aerated soil and a supply of basic compounds. The rain impoverishes the original soil by washing out plant foods and then, by creating waterlogged and therefore anaerobic conditions, prevents the action of normal soil bacteria in breaking down the dead vegetation into humus. Such necessary decomposition does not keep pace with vegetative production by the plants, so that a gradually thickening layer of peat forms. The peat, thus composed of organic matter without lime, is highly acid in character, which is a still further check to bacterial action. Even the run-off water from the poor rocks such as gneiss and Torridonian is charged with unneutralized carbonic acid. With compaction and age, the peat becomes colloidal in texture, a fact of much influence in the behaviour of peat in holding water or being dried. The normal water content of peat as it lies in the bog is as high as 93.5 per cent.
Peat varies in consistency from being highly fibrous to the state of a black amorphous substance, depending on age and the type of vegetation. The Highland crofter is well aware of these details and his methods of winning peat for fuel vary from place to place. Cottonsedge peat is tough and fibrous and can be “footed” (i.e. set up on end to dry in pyramids of four bricks) and handled later with very little loss. Lower, older, amorphous peat is very brittle and cannot be set up.
The ages of the peat deposits have been tentatively fixed as beginning about 7000 B.C. at the close of the Boreal period. The warmish dry climate which grew forests of pine, birch and hazel now became warmish and wet, bringing about destruction of the scrub hazel vegetation by moss. The Atlantic period closed between 5000 and 4000 B.C. and a cooler and somewhat drier sub-Boreal period set in with a rapid development of peat. This continued until near our era which may be termed cold and wet and sub-Atlantic. The peat to-day is still making in some places as on the main bog of Lewis, and receding in others, as in parts east of the Cairngorms where the stumps of forest trees are coming forth as the peat crumbles away. Continual burning on western hills is probably having more influence than we know in checking or denuding the peat which is the only cover the rocks have, but in Lewis there is very little burning, the slopes are gentle and the succession of blanket bog is not being much disturbed, except by cutting for fuel.
The colours of the Atlantic coast are vivid blues and greens and the bright cream of sands. Inland, sombre colours are paramount and the lochans do not reflect the colour of the sky from their dark depths as does the sea above its floor of white sand. But the Hebrides are not all a dark plateau. The southern end of Lewis (Plate VII) and most of Harris are hilly. The Forest of Harris gives us rough going as anywhere in the Highlands and the Clisham rises to a fine peak of 2,622 feet. The red deer which live in these fastnesses are small, but have very well-shaped heads. The pine marten was also to be found there until recently. Its very wildness is the best protection this piece of country has. The lower deer forests of Park and Morsgail are fairly heavily poached of their deer, in an island of such heavy human population.
The Hebridean burns a lot of peat. His peat stacks are far larger than those of the mainland. By cutting peats he is doing two jobs—providing the wherewithal for comfort at the fire, and removing some of the great pervading blanket. He does not come upon bed rock at the foot of the peat banks but on to a layer of boulder clay which, when mixed with the top thin layer of sedge and peat, will shortly turn into fairly good soil providing much better grazing than anything from the top of the peat. The boulder clay came there by glacial action before the peat was laid down. Our Lewisman makes new ground this way and there is no doubt that if the modern mechanical tools such as the scraper and bulldozer were brought into operation on what is commonly called the skinned land, the agricultural scientist could make much good land in Lewis without attempting to conquer the upper layer of the peat.
As might be expected, the bird life of the interior of the Outer Hebrides is poor in variety and scanty, the nesting grey lag geese and red-necked phalarope (Plate XXXIIa) being probably the most interesting members. The geese feed on the crofting ground and on the machair but return into the maze of the interior to nest. The coasts are rich in sea birds, ducks and waders.
